Electrical socket and contacts therefor



S. M- DEL CAMP ELECTRICAL SOCKET AND CONTACTS THEREFOR 2 Sheets-Sheet 1 Aug. 15, 1950 Fill-0d April 23, 1948 INVEN TOR.

I SC/PMM DEL CAM I MAM Aug. 15, 1950 5 DEL CAMP 2,519,121

ELECTRICAL SOCKET AND CONTACTS THEREFOR Filed April 23, 1948 2 Sheets-Sheet 2 F'IGJI.

m sman- SOP/ONE ['2 DEL CAMP,

32 3 BYA M Arrow/vex Patented Aug. 15, 1950 ELECTRICAL socxa'r AND CONTACTS 'rmmaroa Scipione M. Del Camp, Maywood, llL, asslgnor to Cinch Manufacturing Corporation, Chicago, 111., a corporation ot'lllinoia Application April 23, 1948, Serial No. 22,736

Claims. (Cl. 173-328) The present invention relates to lock type electrical sockets and to the contacts therefor, such as are used for the mounting of pronged electrical appliances, for example, electronic tubes for radio and like apparatus, and the inyention aims generally to improve and simplify the construction of such sockets as well as the contact clips therefor.

Many electrical installations employing electronic appliances, for example radio-receiving the contacts thereof. Such prior devices are not adaptable in many installations such as portable radios for automobiles and like use employing miniature electronic tubes, because such tubes do not present clamp-engaging parts.

Furthermore, it has heretofore been the customary practice in electrical sockets for pronged appliances such as thermionic tubes to floatingly J amount the metal prong contacts in an insulating body andrely-upon the resilience of the metal and the contact blades for the-*electrical contact. In such prior constructions the blades do not resist withdrawal of the prongs under forces tending to dislodge them from the contacts, as for example vibration.

One of the primary objects of the present invention is the provision of an improved and simplified electrical socket for pronged appliances such as miniature electronic tubes in which the electrical contacting connection will securely lock the prong inserted therein and hold the appliance in the socket agalnst loosening due to vibration.

A further object of the invention is the provision of an improved' socket and contact for "pronged appliances that'will securely grip and lock the appliance prongswhile providing a good i g and satisfactory electrical contact therewith.

A further object of the invention is the provision. of an improved electrical socket in which -the contact body is rigidly or immovably mounted in the insulating body of the socket and in which the prong contacting blades act as relatively still 2 levers, affording a predetermined resistance to the passage on; terminal prong passed therebetween.

Another object of the invention is the provision of an improved socket and contact arrangement that will insure proper electrical contact with the prongs of the tube or appliance, while allowing for some variation in the spacing of the prongs which frequently occurs in connection withthe readily bendable wire prongs of miniature electronic tubes.

A still further object of the invention is the provision of an improved socket and contact for radio and like apparatus employing miniature electronic tubes in which the contacts are assembled in the socket in an economical and novel manner.

Other aims and objects of the invention will be apparent to persons skilled in the art to which the invention relates from a consideration of the drawings and annexed specification illustrating and describing a preferred embodiment of the invention.

In-the drawings:

Fig. 1 is an enlarged top plan view of an elec- Fig. 1; Y

Fig. 4 is a greatly enlarged transverse sectional view as taken on the line 4-4 of Fig. 3, and illustrating the position of the contact wings prior to engagement by a tube prong;

Fig. 5 is a sectional view similar to Fig. 4 and illustrating the contact wings in engagement with a tube prong.

Fig. 6 is a bottom plan view of the contact and tube prong as illustrated in Fig. 5:

Fig. 7 is a top plan view of the contact clip embodying the invention;

Fig. 8 is an end elevation thereof;

Fig. 9 is a perspective view of the clip shown inFigs.6,7and 8;

Fig. 10 is a sectional view illustrating the contact wings in engagement with a tube prong:

Fig. 11 is a bottom plan view of a socket installation illustrating a second form of socket secured to a supporting panel;

Fig. 12 is a top view (reduced in size) of the installation shown in Fig. 11;

Fig. 13 is a section taken along the line "-18 as will be understood. The discs ll--l2 may be secured in assembly prior to attachment to a support by means such as the rivet l4 which is disposed centrally of the discs.

7 The upper insulating sheet or piece I is provided with a plurality of apertures l6 conformingin number and arrangement to the prongs -2 of the electrical appliance I to be used with the socket. Preferably the apertures I6 are arranged in a circular series of apertures when used for, the reception of multiple pronged miniature electronic tubes.

The insulating plate I2 is provided with a plurality of contact-receiving openings ll prei'erably of elongated rectangular shape and conforming substantially tothe spacing and arrangement of the openings I6 of the plate I I. Preferably, these openings H are elongated radially so as to receive and position elongated blades of a contact disposed radial y of the socket as w l here nafter more fully appear. The plate I2 is additionally provided with contact terminal-receiving openings l8 s aced radially beyond each of the contact receiving openings l1 and preferably these openin s are of elon ated shape with their major axis d sposed at right angles to a radius of the plate passed through the openings II.

The socket member l0 isnrovided with a pl rality of contact members 20, one for each set of apertures l 6-l|, which contacts may be readily assembled with the plate l2 prior to its ssembly with the plate H. The contact members preferably are of sui able construction de-igned to make satisfactory electrical contact with and lock a terminal or circuit prcng of a tube or the like against withdrawal from the socket and preferably include an accessible soldering or wiring terminal. for attachment of a circuit conductor thereto.

One preferred construction of contact is shown particularly in Figs. 6 to 9 inclusive, and comprises a generally L-shaped clip of thin sheet metal of good electrical conducting properties. The contact clip 20 comprises a base portion 2|, preferably flat so as to be confined between the insulating plates ll-l2, which base is p ovided at one end with a prong-receiving aperture 22,

- a pair of opposed angularly extending wings 26 12. The opposite end of the base 2! is formed with an angularly extending wiring terminal or strip 24 adapted to extend through the aperture [8 of the p ate or disc l2.

The opposed wings 25 of the contact body 23 extend angularly from the base 2|, preferably at right angles thereto, for a short distance, preferably not quite equal to the thickness of the plate or disc l2, and thence converge inwardly toward each other to provide opposed contact blades 26 having at their terminal ends, sharp contact edges 2! presented between parallel faces of the contact blades 26 which are disposed angularly to the axis 2-1: of the contact (Figs. 4 and 8) which passes through the aperture 22 and between the blades 26.

The abutting edges 21 of the converging blades 26 present sharp line contacting and gripping edges for engagement with the prong 2 (Fig. 6) of an electrical appliance I, such as a miniature thermionic tube, which prongs 2 frequently are of circular cross section as shown. The contact between the edge 21 and the prong 2 is tangential, as viewed in a transverse plane.

It is important that the blades 26 possess a high degree of stiffness and resistance to separation so as to provide a tight biting edge for engagement with the prong 2. This may be partially effected by the selection of metal from which the contact 20 is formed, but more effectively by restricting flexing movements of the wings 25 outwardly from a point relatively closer to the abutting edges 21 than the base 2|. To this end, the apertures ll of the insulating member l2 are of predetermined width to snugly fit the body portion 23 of the contact and engage the wing portions 25, and thus restrict the outward flexing of the converging blades 26 about iulcra points 28 spaced from the plane of the base 2i. The above construction provides for increased stiffness in the converging blades 26 of the contact blades and a greater tensional grip of the contacting edges 21 with an appliance prong 2 inserted therebetween. As will be apparent, the converging blades act as relatively stiff lever arms movable about fulcra points 28 and aiiord a maximum resistance to the insertion of a cylindrical prong therebetween. Under such resistance the sharp edges 21 tend to scrape oxide from the terminal prongs and insure a satisfactory electrical contact.

Furthermore, as will be noted in Figs. 6 and 8, the length of the terminal ends of the contact blades 26 is substantially greater than the diameter of the opening 22 and said ends are disposed radially in the socket so as to insure locking contact with the prongs 2 of the appliance I even though said rongs may be slightly bent or var ously distorted in a radial direction, as frequently occurs with the readily bendable wire prongs of miniature electronic tubes I. The

manner -in which the relatively long contact' blades operate to provide an effective electrical engagement with a tube pin bent radially outwardly, is illustrated in Fig. 10.

The improved socket and contact of the present invention is particularly desirable and useful for radio and like apparatus employing miniature electronic tubes and subject to extreme vibration such as occurs in automobile and like motor-driven vehicles or carriers. As will be apparent from the above description, each of the terminal prongs 2 of the tube I will be engaged by the opposed converging blades 26 of the contact, the sharp edges 21 of which make electrical contact with and bite into the prong 2. These converging blades 26 are stiffened against separation by the walls of the aperture ll of the disc I2 50 that-the gripping eifect of the blades 26 on the prongs 2 is of a substantial degree. The cumulative gripping effect on each oi the tube prongs is such as to securely lock the tube in the socket against accidental loosening due to vibration, even when the tube is secured in horizontal position to a socket.

Furthermore, as will be apparent to persons skilled in the art, the wire prongs of miniature electronic tubes are readily and easily distorted orbent so that variations in the spacing of the prongs frequently occurs. The provision of the elongated blade 26 of substantially greater length that the invention provides a simple and highly eifective lock-in socket for 'pronged appliances which may be economically manufactured and assembled and which :is particularly useful for securing miniature thermionic tubes in portable radio apparatus subject to extreme vibration.

A modified form of contact member for use in a different typeof socket assemblyis shown in Figs. 11 to 14. Referring to Figs; 13 and 14, the

modified socket member 281: comprises a singl'e circular insulating plate29 having a central aperture 39 for an attaching member such as a rivet and a plurality of elongated rectangular openings 3| which extend radially so as to receive and position the elongated blades of the contact members 32 in a manner identical to that of the openings ll of the first form of my device. The plate 29 is provided with a plurality of contact members 32 which are assembled with the plate prior to attachment of the socket unit to a supporting panel.

The contact members 32 are generally similar to the contact members 20 of my preferred form and comprise a base 33 which is preferably fiat to lie adjacent the upper surface 34 of th plate 29,

which base is provided at one end with a prongreceiving aperture 35. A pair of opposed wings 36 extend in angular relation to the base 33 and form a rectangular body 31 adapted to be positioned snugly in the openings 3i of the plate 29. The opposed wings 36 are formed in the same way as the wings 26 of my preferred form and extend at substantially ri ht angles to th base 33 for a distance substantially equal to the thickness of the plate 29, and thence converge inwardly toward each other to provide opposed contacting blades in the manner of my preferred form. The contacting blades of my second form of contact member cooperate with a tube pin inserted therebetween to secure the pin in flrm electrical engagement with the contact member in the same manner i lustrated and described in connection with my preferred form.,

My second form of fastener member diilers in the construction of the wiring terminals by which the contact members are electrically connected with the circuit leads. Thus, in my second form, the wiring terminal 33 provided at the opposite end of the base 33 of the contact member from the aperture 35, extends outwardly for substantially its entire length in substantially the plane of the base 33. Thus, in this modified construction, the wiring terminals are not bent to extend through apertures in the insulating plate carrying the contact members as in my first form, but instead, project laterally outwardly beyond the peripheral edge of the insulating plate in substantially parallel relation to the projected lateral plane of the plate.

The second form of socket member is. particularly adapted for use with a radio chassis of the *so-called "printed circuit" type. Thus, in Figs.

11 and 12 I have shown one form of support comprising an insulating panel 39 having an aperture 49 for alignment with thecentral aperture 39 of the insulating plate 29 and a plurality of apertures 4| conforming in number and arrangement to the prongs of the tube member to be used with the socket. Preferably the apertures 4| are arranged circularly so as to be in alignment with the apertures 35 of'the contact mem ber carried by the socket unit when the socket is secured to the panel. on the lower side 42 of'the.

tures and 4| of the plate so as to be in proper flxe'd position with ,relation to the terminals 38 of 'the contact members when the socket is secured to the'panel.

The feature of my second form of invention lies in-the construction of the contact member wherein the rectangular prong-engaging body 31 of the contact member operates, not only to eflect the secure gripping engagement with a cooperating tube pin which has been described, but also it is enabled by its shape to cooperate with the walls of the plate opening 3 I 'in a way to maintain the contact member in fixed nonrotative relation to the plate 29 after the contact body 31 has been dropped into the opening 3 I. Thus, with my modifled socket, the contact members are assembled with the insulating plate 29 by dropping the rectangular bodies 31 of the contact members into the respective openings 3|. The wiring terminals 38 of the contact members extend outwardly beyond the peripheral edge of the plate 29 in proper relative spaced position one to another to position their ends 45 in conforming relation to the ends44of the conducting strips 43 of the supporting panel. The relative position of the wiring terminals 38 of the contact members is maintained after the socket unit has been secured to the panel by the rectangular association of the respective contact bodies 31 within the rectangular openings 3! of the plate 29.

In securing the socket member to the supporting panel, the socket member carrying the contact members is moved into adjacent relation to the lower surface 42 of the panel with the openings 35' of the contact members in alignment with the openings 4| of the panel 39. The opening 39.0f the socket plate 29 is now in alignment'with the opening 49 of the panel 39 and the socket is secured to the panel by means of a suitable attaching member such as the rivet 46. During the operation by which the socket member is secured to the panel the outer ends 45 of the wiring terminals of the contact members line up with the ends 44 of the conducting strips 43 so that the wiring strips may be secured in electrical engagement with the conducting strips by soldering the ends 45 to the strip ends 44.

From the above description of my modified form of socket member, it will be apparent that the invention provides a highly efiective, inexpensive arrangement of the socket unit, circuits and supporting panel. The invention presents particularly a simple and eillcient method of.

scope of the invention is best defined in the appended claims.

I claim:

1. A look type electrical contact adapted for engagement with pronged thermionic tubes and the like, said contact comprising a base portion provided with a prong-receiving aperture intermediate the ends thereof, opposed contact blades extending angularly from opposite sides of said base portion laterally on opposite sides of said aperture and having relatively sharp opposed edges at their terminal ends, the terminal ends .of saidcontact blades converging at an acute angle such that the relatively sharp edges thereof are disposed below the aperture on opposite sides of and substantially normal to the axis thereof and adapted to make electrical contact with and lockingly grip a tube prong inserted therebetween, and a wiring terminal extending angularly from said base remote from said blades.

2. A look type electrical contact adapted for engagement with pronged thermionic tubes and the like, said contact comprising a base portion provided with a prong-receiving aperture adiacent one end thereof, opposed contact blades extending angularly from opposite sides of said base portionlaterally on opposite sides of said aperture and presenting oppositely disposed relatively sharp opposed edges at their terminal ends, the terminal ends of said contact blades converging at an acute angle such that the relatively sharp edges thereof are directed inwardly toward each other and disposed below the aperture on opposite sides of and substantially normal to the axis thereof to make electrical contact with and lockingly grip a tube pron inserted therebetween, the widths of said terminal ends being greater than the diameter of said prong-receiving aperture whereby said edges will engage a tube prong inserted through said aperture at an angle to the axis' thereof, and a wiring terminal integral with said base.

3. A locking type electrical contact adapted for engagement'with pronged thermionic tubes and the like, said contact comprising a base portion provided with a prong-receiving aperture, a pair of wings extending angularly from said base portion and laterally opposite said aperture to form a substantially rectangularly shaped body portion, opposed converging contact blades extending angularly from the ends of said wings, the terminal ends of said blades presenting relatively sharp edges adapted by virture ofsaid converging relationship to make electrical-contact with an lockingly grip a tube prong inserted therebetween, and a wiring terminal extending from said base.

4, A locking type electrical contact adapted for engagement with pronged thermionic tubes and the like, said contact comprising a base portion provided with a prong-receiving aperture, a pair of wings extending angularly from said base portion and laterally opposite said aperture to form a substantially rectangularly shaped body portion, opposed convergin contact blades extending angularly from the ends of said wings, the terminal ends of said blades presentin relatively sharp edges adapted by virtue of said converging relationship to make electrical contact with and lockingly grip a tube prong inserted therehetween, the widths of said terminal ends being greater than the diameter of said prongreceiving aperture whereby said edges will engage a tube prong inserted through said aperture at an angle to the axis thereof, and a wiring terminal extending angularly from said base remote from said blades.

5. An electrical socket comprising a body of insulating material provided with a plurality of contact-receiving openings therein, a metal prong-engaging contact for each of said openings comprising a base portion provided with a prongreceivlng aperture a pair of wings extending angularly'irom said base portionand laterally opposite said aperture to form a substantialrectangularly shaped body portion snugly fittin the walls of said openings to be immovable laterally in said body, a pair of opposed converging con-, tact blades extending angularly from the ends of said wings beyond the restricting walls or said openings, the terminal ends of said blades presenting relatively sharp edges in closely adjacent relationship adapted to make electrical contact with and lockingly grip a tube pron inserted therebetween. said converging blades acting as relatively stiff lever arms movable about fulcra points at the juncture of said blades'with said wings to resist passage of a terminal prong therebetween.

6. an electrical socket comprising a plate of insulating material provided with a series of noncircular contact-receiving openings therein, metal prong-engaging contacts for said openings each having a base disposed in parallel substantially abutting relation to one surface of said plate and a terminal portion extending from said base laterally beyond the marginal edges of said plate, each of said contacts having a prong-receiving opening and a pair of wings extending angularly from said base laterally opposite said opening to form a substantially rectangularly shaped prong-engaging body extending from said base into one of said openings, each of said bodies conforming in shape to the shape of said respective openings and snugly fitting the wall of said openings so as to be substantially immovable in said openings, and opposed converging blades extending angularly from opposite sides of each of said bodies, the terminal ends of said blades presenting relatively sharp edges adapted to make electrical contact with and lockingly grip a tube prong inserted therebetween.

7. An electrical socket for miniature pronged thermionic tubes comprising a plurality of superimposed discs of insulating material one of which is provided with a circular series of prongreceiving apertures and the other of which is provided with a circular series of pairs of contactreceiving apertures, one of the apertures of each pair being of elongated rectangular shape disposed with its major axis radially of said disc and adapted to underlie one of the prong-receiving apertures, the other aperture of each pair disposed radially beyond the other aperture thereof and a plurality of contacts each having a prongcontacting and locking portion disposed in the innermost aperture of each pair and a wiring terminal portion extending through the outermost aperture of each pair, said prong-contacting and locking portion of each contact comprising a body portion adapted to be snugly received in said innermost aperture and a pair of converging contact blades extending from said body portion, the terminal ends of said blades presenting relatively sharp edges adapted to make electrical contact with and lockingly grip a tube inserted therebetween.

8. An electrical socket for miniature pronged thermionic tubes comprising a plurality of superimposed discs of insulating material one of which is provided with a circular series of prongreceiving apertures and the other of which is provided with a circular series of pairs of contact-receiving apertures, one of the apertures of prong and a pair of converging contact blades extend-' ing from said body portion below said aperture, the terminal ends of said blades presenting relatively sharp edges adapted to make electrical contact with and lockingly grip a tube prong inserted therebetween.

9. An electrical socket for miniature pronged thermionic tubes comprising a plurality of superimposed discs of insulating material, one of which is provided with a circular series of prong-receiving apertures and the other of which is provided with a circular series of pairs of contact-- receiving apertures, one of the apertures of each pair being of elongated rectangular shape disposed radially of said disc and adapted to underlie one of the prong-receiving apertures, the other aperture of each pair disposed radially beyond the other aperture thereof and disposed normal to a radius passed through the other aperture thereof, a plurality of contacts disposed between said discs each having a prong-contacting and locking portion disposed in the innermost aperture of each pair and a wirin terminal portion extending through the outermost aperture of each pair, said prong-contacting and locking portion 01' each contact comprisin a base portion having an opening therein to receive a tube prong, spaced wings extending angularly from said base portion to form a substantially rectangular body portion, said wings being in contact with the walls of said innermost aperture throughout a substantial portion of the length thereof, a pair of planar contact blades extending angularly from the ends of said wings in converging relationship, the terminal ends of said blades presenting relatively sharp edges adapted to make electrical contact with and lockingly grip a tube prong inserted therebetween, and a single fastening spaced from and disposed centrally of said contacts for securing said discs and contacts in assembled relation.

10. A contact member for a socket for a miniature electron tube, said contact member comprising a piece of sheet metal having an elongated body portion which extends parallel to the base of the socket, a soldering lug portion integral with one end of said elongated body portion, and a pin-receiving portion at the other end of said body portion, said pin-receiving portion including a hole through the said other end of the body portion and a pair of arms depending in the direction of the tube pin for a substantial distance in substantially parallel relation from the a side edges near said end of the elongated body portion at each side of said hole, the free lower ends of said arms being bent sharply inwardly to bear against a tube pin, and being so sloped and shaped as to facilitate sliding of the pin into the contact but to resist movement of the pin out of the contact.

SCIPIONE M. DEL CAMP.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Peters Oct. 27, 1942 

